Return-Path: X-Original-To: apmail-hive-issues-archive@minotaur.apache.org Delivered-To: apmail-hive-issues-archive@minotaur.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id A6FD917B70 for ; Sat, 21 Mar 2015 01:26:38 +0000 (UTC) Received: (qmail 60225 invoked by uid 500); 21 Mar 2015 01:26:38 -0000 Delivered-To: apmail-hive-issues-archive@hive.apache.org Received: (qmail 60204 invoked by uid 500); 21 Mar 2015 01:26:38 -0000 Mailing-List: contact issues-help@hive.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@hive.apache.org Delivered-To: mailing list issues@hive.apache.org Received: (qmail 60189 invoked by uid 99); 21 Mar 2015 01:26:38 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Sat, 21 Mar 2015 01:26:38 +0000 Date: Sat, 21 Mar 2015 01:26:38 +0000 (UTC) From: "Wei Zheng (JIRA)" To: issues@hive.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Updated] (HIVE-9277) Hybrid Hybrid Grace Hash Join MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/HIVE-9277?page=3Dcom.atlassian= .jira.plugin.system.issuetabpanels:all-tabpanel ] Wei Zheng updated HIVE-9277: ---------------------------- Attachment: HIVE-9277.15.patch Upload 15th patch for testing. If this one passes tests, it is ready to be committed. Thanks. > Hybrid Hybrid Grace Hash Join > ----------------------------- > > Key: HIVE-9277 > URL: https://issues.apache.org/jira/browse/HIVE-9277 > Project: Hive > Issue Type: New Feature > Components: Physical Optimizer > Reporter: Wei Zheng > Assignee: Wei Zheng > Labels: join > Attachments: HIVE-9277.01.patch, HIVE-9277.02.patch, HIVE-9277.03= .patch, HIVE-9277.04.patch, HIVE-9277.05.patch, HIVE-9277.06.patch, HIVE-92= 77.07.patch, HIVE-9277.08.patch, HIVE-9277.13.patch, HIVE-9277.14.patch, HI= VE-9277.15.patch, High-leveldesignforHybridHybridGraceHashJoinv1.0.pdf > > > We are proposing an enhanced hash join algorithm called _=E2=80=9Chybrid = hybrid grace hash join=E2=80=9D_. > We can benefit from this feature as illustrated below: > * The query will not fail even if the estimated memory requirement is sli= ghtly wrong > * Expensive garbage collection overhead can be avoided when hash table gr= ows > * Join execution using a Map join operator even though the small table do= esn't fit in memory as spilling some data from the build and probe sides wi= ll still be cheaper than having to shuffle the large fact table > The design was based on Hadoop=E2=80=99s parallel processing capability a= nd significant amount of memory available. -- This message was sent by Atlassian JIRA (v6.3.4#6332)